2 Replies Latest reply on Nov 12, 2013 3:46 PM by Sankar

    Motherboard support for Power limit

    Sankar

      I have a system with i5-2500K sandy bridge processor. I am trying to leverage the power limit registers offered by this processor to measure the energy (and average power) of the cores and the on-chip GPU - I want to power cap the cpu cores and the gpu cores as part of some experiments that I am running. However the BIOS in my chipset does not enable these features. Could anyone suggest any chipset model that would allow me to use the power limit registers?

        • 1. Re: Motherboard support for Power limit
          sylvia_intel

          Sankar, the Intel(R) Core(TM) i5-2500K Processor supports the power limit registers but they might be locked by the BIOS.

           

          Check the Lock Bit described on page 14-23 of volume 3B of the Software Developer’s Manual located at the following website: http://download.intel.com/products/processor/manual/253669.pdf

           

          You can use third party software applications to change these settings but we do not recommend their use and we cannot be held responsible for any damage caused by using or installing 3rd party tools.

          • 2. Re: Motherboard support for Power limit
            Sankar

            I have a motherboard based on Z77 chipset that supports overclocking. I read the msr registers and made sure that the lock bit is not set. However, the power limit feature is still not working.

             

            I try to set a new power cap (lower than the native) using the power limit registers. But the experiments show that the program runs at regular performance (It is supposed to be running at reduced performance after the power cap). I am not sure why this feature isn't working.